/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.graph.drivers.output;

import org.apache.flink.api.java.DataSet;
import org.apache.flink.graph.asm.dataset.ChecksumHashCode;
import org.apache.flink.graph.drivers.parameter.BooleanParameter;

import java.io.PrintStream;

/**
 * Print hash of algorithm output.
 *
 * @param <T> result Type
 */
public class Hash<T>
extends OutputBase<T> {

	private BooleanParameter printExecutionPlan = new BooleanParameter(this, "__print_execution_plan");

	@Override
	public void write(String executionName, PrintStream out, DataSet<T> data) throws Exception {
		ChecksumHashCode<T> checksumHashCode = new ChecksumHashCode<T>().run(data);

		if (printExecutionPlan.getValue()) {
			out.println();
			out.println(data.getExecutionEnvironment().getExecutionPlan());
		}

		ChecksumHashCode.Checksum checksum = checksumHashCode
			.execute(executionName);

		out.println();
		out.println(checksum);
	}
}
